Automotive Powertrain Trends

New cars and trucks may look different on the outside, but the biggest changes are under the hood. Automakers are upgrading engines and transmissions to increase gas mileage and meet stricter fuel economy standards. Today’s gasoline engines burn fuel more efficiently than in the past. They are also smaller and lighter, allowing other components to be downsized for even more fuel savings. New automatic transmissions offer up to ten gears, and a few even use GPS data to anticipate hills and automatically shift to the best ratio. Modern diesel engines have advanced emission controls that eliminate exhaust smoke and odor. And, today’s new-car market offers an array of hybrid- and full-electric vehicles that offer unique driving characteristics and reduced fuel costs. In coming years, expect more models to run on hydrogen, compressed natural gas, propane and ethanol-gasoline blends.

Automakers Overhaul Powertrains to Go Green

New car shoppers haven’t had this many engine and transmission choices since the early days of the automobile. Why? Because federal fuel economy and gas emission standards require that U.S. automakers achieve an average fleet fuel economy rating of 35.5 per gallon by 2016, and 54.5 mpg by 2025. Here are some noteworthy powertrain innovations to help meet these goals:

Better internal combustion engines: Gasoline still powers 95 percent of all cars sold in the United States. Car companies are building advanced gasoline and diesel engines that burn fuel more efficiently to improve gas mileage.

Shrinking engine size: Automakers are adopting smaller four- and six-cylinder engines, and a few have put three-cylinder engines in their smallest models. Smaller and lighter engines mean other components such as suspensions and brakes can shrink too, leading to even more fuel savings.

Transmissions with additional forward gears: It’s not uncommon for automatic transmissions in new cars to have six to ten forward gears. The extra ratios help engines operate at peak efficiency in a wide range of driving conditions. One automaker even offers automatic transmissions that use GPS data to anticipate hills and automatically shift to the best gears.

Better hybrids: Hybrid electric vehicles that combine a gasoline engine with one or more electric motors offer the best fuel economy with the least demand on traction battery power. Newer models have better system controls and use Atkinson-cycle engines for greater efficiency. One of the best-known HEVs is the Toyota Prius, which has been on the market for 15 years and currently is the single best-selling passenger car in California.

Fuel cell electric vehicles: Several automakers, including Toyota, Hyundai and Honda, have made fuel cell electric vehicles powered by hydrogen available in the United States. These cars produce no emissions other than water vapor and heat, and compared to battery electric cars take minutes rather than hours to refuel. Early models will be offered for lease in limited markets, as refueling stations are few and far between.

Consider All the Costs When Buying a Green Car

Tax breaks make alternative-fuel vehicles attractive, but new-car shoppers need to consider all the costs to determine the true price of ownership over time.

Green cars run on unconventional fuels or minimize greenhouse gas emissions other ways. They include cars with advanced internal combustion engines that use less fuel, hybrid- or full-electric cars and hydrogen fuel-cell vehicles. Depending on the model, you can get up to $7,500 in federal tax credits and state tax credits of $500 to $6,000.

Tax credits come in handy, as green car sticker prices can be substantially higher than what you pay for vehicles with conventional gas engines. A Brown University study found hybrid electric cars cost an average $8,494 more than regular models even though they save only $3,505 in fuel costs over five years. A separate report from the Center for Automotive Research estimates drivers will pay $2,750 to $5,270 more for vehicles that meet future fuel economy and emissions standards.

Green car repairs may be challenging and more expensive because mechanics need special tools and training to work on hybrid powertrains. Also, filling stations for cars running on 85-percent ethanol-gasoline blends or other alternative fuels remain scarce. Owners of electric vehicles sometimes install home charging stations, but units can be costly and require professional installation, and a home’s electrical service must have enough capacity to support the extra load.

With stricter federal fuel economy standards on the way, more drivers will investigate alternatives to gasoline-powered cars. If you’re one of them, consider all the costs before deciding to go green.

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